Elastin is a major component in pulmonary and vascular tissues. Detailed examination of elastin obtained from anatomically defined portions of lung and aorta by mild non-hydrolytic procedures has indicated that defective maturation of elastins may have a significant role in the etiology of pulmonary and vascular disease. Methods of maturation analysis developed in the applicant's laboratory have progressed to the stage where a critical judgment relating elastin crosslinking to the pathological consequences of various disorders is possible. Another aspect of the research in progress deals with an apparent relationship in various soft tissues between elastin and certain dystrophic and metastatic calcifications which have a protein matrix containing the newly discovered amino acid gamma-carboxyglutamate. In this regard, for example, we have recently shown that the hard calcified plaques,closely associated with elastin as seen in atherosclerotic aortas, have a matrix protein containing gamma-carboxyglutamate. This new amino acid is produced on specific proteins such as found in four blood clotting proteins, a bone protein (osteocalcin, discovered in our laboratory) and in various ectopic calcifications by a specific post-translational carboxylation reaction which is vitamin K dependent. Accordingly, we wish to further explore the thesis that cellular, metabolic and structural relationships exist in normal and pathological elastic tissue which can promote vitamin K dependent calcification. It is our thesis that elastin deposition, maturation and its possible promoter role in calcification contribute to the etiology and consequence of various pulmonary and vascular disorders.